$("#comment-btn").click(function(){
	var book_id = $("#book_id").val();
	var uid = $("#uid").val();
	var uname = $("#uname").val();
	var comment = $("#comment").val();
	$.post("/comment?id="+book_id,{uid:uid,uname:uname,comment:comment},function(result){
		//alert(result);
		$("#all_comment").append(result);
	},"html");
});